Improvement in dental drills



UNITED STATEs CHANDLER POOR, OF DUBUQUE, IOWA.

IMPROVEMENT IN DENTAL DRlLLS.

Specification forming part of Letters Patent No. 118,268, dated August22, 1871.

To all whom 'it may concern:

Beit known that I, CHANDLER POOR, of Dubuque, in the county of Dubuqueand State of Iowa, have invented a new and Improved Dental Bur-Lathe;and I do hereby declare that the following is a full, clear, and exactdescription thereof, which will enable others skilled in the art to makeand use the same, reference being had to the accompanying drawingforming part of this specification.

This invention relates to a new and improved apparatus for revolving thebur-ring Or millingtools used by dentists for drilling' and cleaningcavities in decayed teeth preparatory to filling', finishing off, andpolishing the surface of the material used for filling' or plugging',cutting, trimming, polishing, and finishing artificial teeth and plateof India rubber or metal.

My invention consists in improving dental burlathcs, as hereinafterfully described and subsequently pointed out in the claims.

Figure lis a side elevation of my improved machine partlyT sectioned.Fig. 2 is a front elevation, and Fig. 3 is a longitudinal section of theholder for the bur-mandrel.

Similarletters of reference indicate corresponding parts.

A is a driving-shaft, with a balance-wheel, B, crank O, and foot-treadleD for generating motion for operating the bur-man drel. This shaft ismounted in bearings suitably arranged either on the foor or a bed-plateto extend from'the back of the Operating-chair, where it is preferableto have the foot-treadle, to the front of said chair, where the stand Eis to be for supporting the spindle F, which operates the bur-mandrel infront of the patient. This stand is pivoted at G so as to vibrate in thevertical plane of the shaft. Said shaft is connected in said axis G by auniversal joint with a short shaft, X, mounted at the outer end in thelower part of stand E, and carrying a multiplying-pulley, H, from whichthe spindle F at the top is driven by a belt, I. This spindle isconnected by a cord, J, of catgut, with the end of mandrel K oppositethe one carrying the bur L, a-nd said spindle is mounted in a tubularhandle, M, by which it is held to the work by the operator while rotarymotion is imparted to it. This tubular handle is preferably composed ofthe main tube a and the end pieces b and d, the said end pieces havingsmall holes for the reduced portions of the mandrel, andscrewing intopart a against the shoulders ofthe mandrel so as to confine it againstend motion.

The part d is provided with a bell-mouth-shaped cavity extending beyondthe end of the mandrel,

which is intended to serve as a guide for controlling, to some extent,the flexible cord which assumes the form of a bow and swings around theaxis ofthe mandrel -when not drawn out taut by the operator.'A The standE, being intended to swing' toward or from the patient, is provided witha weighted cord, N, to pull it away from the patient, said cord workingover a pulley, O. The movement of the stand toward the patient iseffected by the operator pulling it by the handle M and cord J. ,I

The drivin g-shaft maybe arranged perpendicular to the position hererepresented, and in the axis G whereon the stand E vibrates, and begeared by bevel-wheels with the shaft of wheel Hin such cases as mayrequire it or make it preferable; for instance, when such chairs areused as will not admit of the shaft passing under them. In such anarrangement the universal joint by which said driving-shaft is connectedto the shaft of wheel H will not be required. It will be seen that bythis arrangement a very efficient means Of working the bur is provided,wh ich at the same time allows all the freedom needed for holding anddirecting the tool.

I am aware that ratan and corded wire have been used as a flexibleconnection, but these I claim as no part of my invention.

Having thus described my invention, I claim as new and desire to secureby Letters Patent- 1. In combination with abrir-carrying' mandrel, K,and rotating spindle F, the intermediate catgut J, applied as and forthe purpose specified.

2. A swinging frame, E, to support the pulley mechanism, journaled inuprights, and counterbalanced by weighted cord N, as and for the purposespecified.

Witnesses: CHANDLER POOR.

TIMOTHY MASON, THOMAs HAEDLE.

